To tie a shirt, preferable a white long sleeve dress shirt around a girl's waist, just ahead of her hips. Her hips lock it in place, so that during doggy-style intercourse the shirt can be used as a handle to allow for more forceful thrusts. Partucularly useful when intoxicated.

Thanks for lending me your new dress shirt, I'm sorry it got stretched and stained when I used it to put an Irish handle on your sister.